This is a House Finch with abnormal pigmentation
(leucism.amelanism..whatever you want to call it). In other words, what
sometimes has been termed partial albinism. The oddity is how symmetrical
and complete it is on the ear coverts, but also check out that some of the
hind neck feathers are white. Otherwise in structure and coloration it is a
perfectly fine House Finch. The shape and structure being perfect for House
Finch excludes the possibility that this is some type of hybrid. Note that
House Sparrows are true sparrows (Passeridae), but the Sparrow-junco hybrids
have been between members of the Emberizidae, so White-throated Sparrow x
Dark-eyed Junco. This is where the generic term sparrow becomes misleading.
House Sparrows are exceedingly unlikely to hybridize with members of an
entirely different family of birds, such as Emberizids.
Half Moon Bay, California
Field Guides - Birding Tours Worldwide
From: SFBirds@... [mailto:SFBirds@...] On Behalf Of
Sent: Monday, December 15, 2008 7:32 PM
Subject: [SPAM] [SFBirds] Funny Finch
My totally uneducated guess of the weird finch with white cheeks is
either some Albino, or, a House FinchxHouse Sparrow cross. I have no
idea if these two mix. I have read of Sparrow-Junco hybrids, but I do
not know if that is confirmed.
Maybe some one knows.
Perhaps this bird should be trapped and studied?